I wouldn't call them good solutions, because of lack of volume, but coinmkt.com is based in the US. I may try to use Ripple to deposit and withdraw with Bitstamp.net, but I'm not quite sure how great an idea that is yet.

There's also a Canadian exchange vaultofsatoshi.com. I think that is also suffering from low volume.

I did notice that campbx was extremely low volume yesterday (picking up today), probably due to the problems from Monday.